Common problems and solutions of laser cutting metal plate

Common problems and solutions of laser cutting metal plate

As a material cutting method, laser processing has been increasingly accepted by sheet metal producers. Laser cutting has become one of the most important metal processing methods in modern enterprises. Laser cutting is the use of a focused high-power density laser beam to irradiate the workpiece, so that the irradiated material is melted, vaporized, ablated or reached the ignition point. At the same time, the molten material is blown away by the high speed air flow with the coaxial beam, thus the cutting of the workpiece is realized.

There are several common problems in laser cutting of domestic medium thick metal plates.

The problem of perforation of thick carbon steel plate

In the thick plate processing, the time of perforation accounts for a large proportion, and laser manufacturers have developed their own piercing schemes. More typical is the energy hole (hole), the advantage of this method is fast (1 second, take t16mm as an example – the following is the same). But the defect is the influence of small shape processing. The energy injected into the perforation increases the temperature of the plate and affects the next whole cutting process. The small power pulse can be used for a long time (12 seconds), resulting in a decrease in the efficiency of cutting.

Quality problem of cutting surface

The cutting section problem is often encountered when machining medium and heavy plates, and the quality of such finished products is questioned. It is also accompanied by excessive burning and serious sticky slag, so that it can not reflect the value of high price laser processing machine from other cutting tools.

The problem of the stability of the whole plate machining

In the whole plate processing of domestic steel, the phenomenon of poor local area processing often occurs. This phenomenon is sometimes very random, even if the laser cutting machine is in good condition. In order to deal with local fault products and greatly affect the whole progress of work, the failure of this unknown reason is also given some analysis and countermeasures.


There are the following solutions to the above problems.

1. peak perforation. As the name implies, it is to use the high peak value pulse laser with small duty ratio, with the non fuel spray on the surface of the material to remove the attachment of the hole edge, and control the reasonable frequency edge perforation of the edge of the pulse.

2. for carbon steel, the important factor to change the cutting section is to control the heat input to the plate and realize the combustion of the laser irradiation part. For stainless steel, the important factor of the cutting section is the improvement of the beam and the utilization of the gas.

3. the scheme of processing stability. Using the equal length optical path (equal length of light propagation path between the light source and the processing head within the machinable area), the depth of focus change can be reduced. So that the spot and the focal depth are the same.

More info:

Website: www.sublistarlaser.com

Company Name: Fei Yue Digital Technology Co.,LTD

Tel: 86-025-86628894

E-mail: sales@sublistarlaser.com

Whatsapp: +86 18252072197

Address: Central Road 323, Nanjing, Jiangsu, China

Method for determining focal position in laser cutting in industrial production

Method for determining focal position in laser cutting in industrial production

A simple method for laser cutting to determine focal position in industrial production.

1. Printing method. Move the cutting head from top to bottom, print the laser beam on the plastic plate, and print the minimum diameter as the focus.

2. Oblique plate method. The plastic plates are placed horizontally on the vertical axis to pull horizontally. The minimum point for finding the laser beam is the focus.

3. The blue spark method. Remove the nozzles, blow the air, beat the pulse laser on the stainless steel plate, so that the cutting head moves from top to bottom until the blue sparks are the focal points.

In order to reduce the change of the focal spot size caused by the change of the beam size before focusing, the manufacturers of laser cutting machines at home and abroad provide some special devices for the user to choose.

1. Parallel light tube, this is a common method. The parallel light tube is extended to the output of the CO2 laser. The diameter of the beam after the beam expansion becomes larger and the divergence angle becomes smaller, so that the beam size of the near end and the far end in the cutting range is close to the same.

2. A lower independent axis of the moving lens is added to the cutting head, so that the Z axis from the distance from the control nozzle to the material surface (standoff) is two independent parts. When the machine tool worktable moves or the optical axis moves, the beam moves from the near end to the far end F axis, so that the light spot diameter of the beam is consistent in the whole processing area.


More info:

Website: www.sublistarlaser.com

Company Name: Fei Yue Digital Technology Co.,LTD

Tel: 86-025-86628894

E-mail: sales@sublistarlaser.com

Whatsapp: +86 18252072197

Address: Central Road 323, Nanjing, Jiangsu, China

Cause and solution of cutting edge burning of metal laser cutting machine

Cause and solution of cutting edge burning of metal laser cutting machine

When laser cutting sheet metal parts, a lot of heat will be generated, and the heat will not be spread in time. In the processing of small holes, the metal laser cutting machine can be cooled on the outside of the hole. The small hole on the inside of the single hole is small because the heat can be diffused. The heat is too concentrated to cause excessive burning and slag. In addition, in the thick plate cutting, the molten metal accumulated on the surface of the material and the accumulation of heat can make the auxiliary air flow disorder and heat input too much, thus causing excessive burning, causing the phenomenon of burning edge.

So how to solve the problem of edge burning and slag hanging?

The solution for overburning when laser cutting carbon steel for small hole cutting. In the cutting of carbon steel with oxygen as the auxiliary gas, the key to solve the problem lies in how to restrain the production of oxidation heat. The method of auxiliary oxygen or delayed switching can be used to cut auxiliary air or nitrogen. This method can process small holes whose upper limit is 1/6 thick plate.
The pulse cutting condition of low frequency and high peak output power can reduce heat output and optimize cutting conditions. Setting the condition as a single pulse laser beam, high peak output and low frequency condition of high energy intensity can reduce the accumulation of molten metal on the surface of the material during the perforation and reduce the output of heat.

Solutions for laser cutting of aluminum alloy and stainless steel. The auxiliary gas used in the processing of such materials is nitrogen, which will not burn edges in cutting. However, due to the high temperature inside the small hole, the phenomenon of slag sticking in the inner side will be more frequent.
The solution to this problem is to increase the pressure of auxiliary gas. The conditions are set as high peak output and low frequency pulse conditions. When auxiliary gas is used in air, it will not burn as much as when nitrogen is used. However, it is easy to appear slag at the bottom. It is necessary to set the conditions for high auxiliary gas pressure, high peak output and low frequency pulse conditions.

More info:

Website: www.sublistarlaser.com

Company Name: Fei Yue Digital Technology Co.,LTD

Tel: 86-025-86628894

E-mail: sales@sublistarlaser.com

Whatsapp: +86 18252072197

Address: Central Road 323, Nanjing, Jiangsu, China